Autumn stopover ecology of the Blackpoll Warbler (Dendroica striata) in thorn scrub forest of the Dominican Republic

1999 ◽  
Vol 77 (7) ◽  
pp. 1147-1156 ◽  
Author(s):  
Steven C Latta ◽  
Christopher Brown
Keyword(s):  
Dominican Republic ◽  
Weather Conditions ◽  
Single Species ◽  
Stopover Ecology ◽  
Behavioral Observations ◽  
Lepidopteran Larvae ◽  
Fat Stores ◽  
Fat Score ◽  
Dendroica Striata ◽  
Scrub Forest

We used mist-netting, color-banding, resighting, and behavioral observations to study the autumn stopover ecology of migrating Blackpoll Warblers (Dendroica striata) in coastal thorn scrub forest in the area of Cabo Rojo, Pedernales Province, Dominican Republic. Blackpoll Warblers were the most abundant migrant present in this habitat throughout most of October 1997. Warblers stopping over in this habitat were generally young with moderate to large fat stores. No lean birds (fat score = 0) were captured. Our behavioral observations suggest that Blackpoll Warblers are flexible in terms of social organization, with birds associating in single-species flocks and in mixed-species aggregations, but single birds were also recorded. Foraging activity consisted primarily of gleaning from leaves and was focused on lepidopteran larvae, whose high abundance coincided with Blackpoll Warbler arrival. We suggest that most stopover Blackpoll Warblers were not weakened individuals searching for emergency energy stores but were forced down owing to unfavorable weather conditions for migration; others may have been taking advantage of landfall on the south coast of Hispaniola for daytime rest before continuing across the Caribbean Sea to South America. Coastal thorn scrub forest of Hispaniola appears to be a preferred stopover habitat for a variety of migrants, providing a place to rest and replenish energy reserves following transoceanic flight.

scholarly journals Definitive Prebasic Molt of Gray Catbirds at two Sites in New England

The Condor ◽  
2000 ◽  
Vol 102 (4) ◽  
pp. 894-904 ◽  
Author(s):  
Colleen Dwyer Heise ◽  
Christopher C. Rimmer
Keyword(s):  
New England ◽  
Rhode Island ◽  
Natural Science ◽  
Site Specific ◽  
Behavioral Observations ◽  
Fat Stores ◽  
Dumetella Carolinensis ◽  
Males And Females ◽  
Per Se ◽  
Second Year

Abstract We studied the pattern and timing of prebasic molt in adult Gray Catbirds (Dumetella carolinensis) at two New England sites: Block Island, Rhode Island (BIRI), and the Vermont Institute of Natural Science (VINS) in Woodstock, Vermont. Catbirds at VINS initiated molt earlier and molted at a significantly slower rate than catbirds at BIRI. Mean individual molt durations spanned approximately 54 days at VINS and 44 days at BIRI. The two groups ended molt at about the same time. Catbirds at VINS were more variable in the timing of their molt. At both sites, second-year catbirds began and ended molt significantly earlier than after second-year catbirds. Males and females did not differ significantly in their rate or timing of molt at either site. Behavioral observations at BIRI indicated that catbirds spent less time foraging during the heaviest period of molt, but that increased foraging during late molt stages coincided with increases in fat stores, indicating overlap of molt and hyperphagy. We found no evidence that Gray Catbirds at either site departed for migration prior to completing remigial molt. The later molt schedule of BIRI birds likely resulted from the extended breeding season of some individuals. We believe that molt schedules at the two sites were influenced less by latitude per se than by site-specific differences in vegetation, food abundance, and temperature, resulting from differing elevations and conditions of coastal and inland environments.

The primary production of aldabra atoll, with reference to habitats used by Giant Tortoises

1983 ◽  
Vol 302 (1109) ◽  
pp. 167-199 ◽  
Keyword(s):  
Primary Production ◽  
Standing Crop ◽  
Single Species ◽  
Structural Heterogeneity ◽  
Turnover Rates ◽  
Net Production ◽  
Wooded Area ◽  
Leaf Turnover ◽  
Scrub Forest

This paper reports on the seasonal changes of standing crop and production in habitats used by a high-density population of giant tortoises on Aldabra atoll. The study had two main aims: first to investigate the primary production of a raised coral atoll (to our knowledge the first such study) and secondly to provide base data for a study of the interactions of a large reptilian herbivore (the giant tortoise) with its food supply and environment. Environmental heterogeneity made it necessary to measure separately the standing crop and the above-ground net production of different components of the vegetation; these components were usually single species or small groups of species of plants. Measurements of these components were then combined with cover data for the same components in selected places to illustrate the seasonal and spatial variability of primary production on Aldabra. Standing crop biomasses were estimated from harvest samples. Methods for production estimates varied with the component studied, but included harvest difference methods, repeated clipping of the same plots and direct measurement of leaf turnover rates on marked shoots. These methods are compared where appropriate. Net annual above-ground production varied between plant types from 3165 kJ per square metre of plant for ‘tortoise turf’ to 47700 kJ m -2 for Cyperus ligularis , a robust perennial sedge. Total above-ground annual net production of different habitat types (bare ground and rocks between plants being taken into account) varied from 9100 kJ m -2 in a thinly wooded area with high tortoise turf cover (‘open mixed scrub’) to 28200 kJ m -2 in an area of thick scrub forest (‘groves’). The seasonality of production and standing crop also varied considerably between habitats, owing to the role of different components of the ground layer and shrub cover. These results are discussed in terms of the roles of environmental and structural heterogeneity in setting primary production and of the tortoises themselves in their interactions with the vegetation via trampling and grazing. The effect of this heterogeneity on sampling strategies and results is also assessed.

scholarly journals The risks of warm nights and wet days in the context of climate change: assessing road safety outcomes in Boston, USA and Santo Domingo, Dominican Republic

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
José Ignacio Nazif-Munoz ◽  
Pablo Martínez ◽  
Augusta Williams ◽  
John Spengler
Keyword(s):  
Climate Change ◽  
Dominican Republic ◽  
Road Safety ◽  
Warm Season ◽  
Weather Conditions ◽  
Heavy Precipitation ◽  
Traffic Fatalities ◽  
Santo Domingo ◽  
Temperature And Precipitation ◽  
Precipitation Events

Abstract Background There remains a dearth of cross-city comparisons on the impact of climate change through extreme temperature and precipitation events on road safety. We examined trends in traffic fatalities, injuries and property damage associated with high temperatures and heavy rains in Boston (USA) and Santo Domingo (Dominican Republic). Methods Official publicly available data on daily traffic outcomes and weather conditions during the warm season (May to September) were used for Boston (2002–2015) and Santo Domingo (2013–2017). Daily maximum temperatures and mean precipitations for each city were considered for classifying hot days, warm days, and warm nights, and wet, very wet, and extremely wet days. Time-series analyses were used to assess the relationship between temperature and precipitation and daily traffic outcomes, using a quasi-Poisson regression. Results In Santo Domingo, the presence of a warm night increased traffic fatalities with a rate ratio (RR) of 1.31 (95% CI [confidence interval]: 1.00,1.71). In Boston, precipitation factors (particularly, extremely wet days) were associated with increments in traffic injuries (RR 1.25, 95% CI: 1.18, 1.32) and property damages (RR 1.42, 95% CI: 1.33, 1.51). Conclusion During the warm season, mixed associations between weather conditions and traffic outcomes were found across Santo Domingo and Boston. In Boston, increases in heavy precipitation events were associated with higher traffic injuries and property damage. As climate change-related heavy precipitation events are projected to increase in the USA, the associations found in this study should be of interest for road safety planning in a rapidly changing environment.

Changes in insect populations in the field in relation to preceding weather conditions

1951 ◽  
Vol 138 (890) ◽  
pp. 130-156 ◽  
Keyword(s):  
Minimum Temperature ◽  
Population Change ◽  
Geometric Mean ◽  
Light Trap ◽  
Population Level ◽  
Weather Conditions ◽  
Single Species ◽  
Great Accuracy ◽  
Insect Population ◽  
Logarithmic Scale

An attempt has been made to measure changes in a mixed insect population under natural conditions in the field, and to see to what extent they are quantitatively related to previous weather conditions. To obtain a measure of the population, insects were caught in a light-trap at Harpenden, about 25 miles north of London, every night for four years from 1933 to 1937, and again for four years from 1946 to 1950. In all about 1,440,000 insects, mostly Diptera, were captured on about 2850 nights. The measure of population level in any one month was the geometric mean catch per night, obtained by calculating the arithmetic mean of log ( n + 1), where n is the number of insects caught in one night. This figure has to be corrected for the effect of prevailing weather conditions on activity. The departure of each month, on the logarithmic scale, from the average value for all repetitions of the same month gives a measure of how the population in this particular month is differing from the level to be expected for that time of the year. These departures were then made the basis of six-factor multiple regressions, in which the population change was the dependent variable, and the rainfall and minimum temperature departures from normal in each of the three preceding months were the independent variables. It is shown that a very high proportion of the mean changes of the population in the field can be accounted for by the effect of rainfall and minimum temperature in the three previous months. An examination of the regressions in the different seasons shows that rainfall has a high positive effect in the summer and autumn but little or no effect in the winter. Minimum temperature, on the contrary, has its lowest effect in the summer, so that the relation between population and minimum temperature one month previous is negative in the summer, and with temperature two months previous is negative in the autumn. The analysis of the available data has so far only been carried out on the total insect population, against rainfall and minimum temperature. Work is continuing on other weather conditions, other time intervals, and also on special groups of insects, but it is unlikely that the method can be applied with any great accuracy in the near future to single species of insects.

scholarly journals Inter-annual weather variability can drive the outcome of predator prey match in ponds

2015 ◽  
Vol 36 (2) ◽  
pp. 97-109 ◽  
Author(s):  
Timm Reinhardt ◽  
Sebastian Steinfartz ◽  
Markus Weitere
Keyword(s):  
Prey Availability ◽  
Weather Conditions ◽  
Single Species ◽  
Growth Conditions ◽  
Initial Growth ◽  
Ephemeral Ponds ◽  
Complete Life Cycle ◽  
Compensation Mechanisms ◽  
In The Beginning ◽  
Salamander Larvae

The matching of life-history-events to the availability of prey is essential for the growth and development of predators. Mismatches can constrain individuals to complete life-cycle steps in time and in ephemeral habitats it can lead to mortality unless compensation mechanisms exist. Here we measured the performance of a population of European fire-salamanders (Salamandra salamandra) and their prey in ephemeral ponds. We analysed how short time inter-annual variability of yearly rainfall and temperature (two consecutive years, 2011 and 2012) affects matching of predator and prey and how two different weather scenarios influenced the predator’s population structure. A single species (larvae of the mosquito Aedes vexans) dominates the prey community here, which occurs in high quantities only in the beginning of the season. When the occurrence of prey and predator matched during a period of sufficiently high temperatures (as in 2011), initial growth of the salamander larvae was high and population size development homogeneous. At low temperatures during matching of predatory and prey (as in 2012), the initial growth was low but the salamander larvae developed into two distinctly different sizes. Further, some individuals in the large cohort became cannibalistic and initial size differences increased. As a result, the latest (smallest) cohort disappeared completely. Temperature measurements and estimation of maximal growth rates revealed that temperature differences alone could explain the different early development between years. Our data show that weather conditions (rainfall; temperature during early growth phase) strongly determined the performance of salamander larvae in ponds. Our data also add to the match-mismatch concept that abiotic growth conditions (here: low temperature) could prevent efficient conversion of prey- into predator-biomass despite high prey availability.

The genus Cittarium (Vetigastropoda: Trochoidea) in the Upper Miocene of the Dominican Republic with the description of a new species

2015 ◽  
Vol 89 (4) ◽  
pp. 589-593
Author(s):  
Bernard Landau ◽  
Gijs C. Kronenberg ◽  
Carlos M. da Silva
Keyword(s):  
New Species ◽  
Dominican Republic ◽  
West Indies ◽  
New Record ◽  
Single Species ◽  
The West ◽  
Upper Miocene ◽  
Upper Oligocene ◽  
Tropical America ◽  
A New Species

AbstractToday, the marine gastropod genus Cittarium is present only in the West Indies faunas, represented by a single species C. pica, also known from the Pleistocene of Bermuda. Herein Cittarium praepica n. sp. is described from the Upper Miocene Cercado Formation of the Dominican Republic. This is the oldest fossil record for the genus in the eastern Tropical America. The new species is compared to the Pleistocene to Recent Caribbean C. pica and to C. maestratii Lozouet, 2002 of the Upper Oligocene of France. The importance of this new record for the geological history and the biogeography of the genus are discussed.

SPECIES AND VARIETIES OF PERENNIAL GRASSES FOR MAKING OF STABLE LAWN COMMUNITIES

2020 ◽  
Author(s):  
Nadezhda Yufereva ◽  
Maria Shchannikova
Keyword(s):  
Perennial Ryegrass ◽  
Weather Conditions ◽  
Single Species ◽  
Perennial Grasses ◽  
Correct Selection ◽  
Seeding Rate ◽  
Red Fescue ◽  
Adverse Weather ◽  
Selection Of Species ◽  
Number Of Shoots

The correct selection of species and varieties of perennial grasses for making of stable lawn herbages is an important task for the researchers. Research of lawn herbages was conducted for six years period on the experimental field of the Vyatka State Agricultural Academy. As a result, were specified domestic varieties of lawn grasses which suit for the conditions of the Kirov region and show resistance to adverse weather conditions observed during the years of research. Red fescue Sigma and meadow grass Vagant and Dar forming lawns from good to excellent quality. The number of shoots per unit area for the sixth year for these species and varieties is 12.6–15.9 thousand pieces per square meter, 6.5–6.8 thousand pieces per square meter and 4.1–5.0 thousand pieces per square meter respectively. These species and varieties can be recommended for making of stable single–species lawn herbages. The seeding rate can be reduced in comparison to the recommended one. Perennial ryegrass in the conditions of the Kirov region shows low winter hardiness, the number of shoots declines since the third year of life and the number of undesirable plant increases. However, the perennial ryegrass has superior lawns in the year of sowing. Therefore, this species can be used for the quick making of lawns with a usable life no more than two years.

The first records of fossil Corethrellidae (Diptera)

1991 ◽  
Vol 22 (4) ◽  
pp. 457-463 ◽  
Author(s):  
A. Borkent ◽  
R. Szadziewski
Keyword(s):  
New Zealand ◽  
Dominican Republic ◽  
East Germany ◽  
Single Species ◽  
Sister Group ◽  
The Other ◽  
Phylogenetic Position ◽  
Male Adult ◽  
The Family

AbstractThe first fossil Corethrellidae, represented by two male adult Corethrella, are described. One, C. prisca sp. n., is from Saxonian amber collected in East Germany and is of Miocene age (22 Ma). The other, C. nudistyla sp. n., is from Dominican Republic amber and is 15-40 million years old. The family Corethrellidae, because of its phylogenetic position, is presumably of at least Jurassic age. The fossils are typical members of the genus Corethrella and belong to a clade which is the sister group of a single species in New Zealand.

Taxonomic problems in the Aphanogmus hakonensis species complex; (Hymenoptera: Ceraphronidae) common hyperparasitoids in biocontrol programmes against lepidopterous pests in the tropics

1996 ◽  
Vol 86 (4) ◽  
pp. 419-422 ◽  
Author(s):  
Andrew Polaszek ◽  
Paul Dessart
Keyword(s):  
Biological Control ◽  
New Species ◽  
Species Complex ◽  
Single Species ◽  
Morphological Studies ◽  
Lepidopteran Larvae ◽  
Two New Species ◽  
Control Programmes ◽  
Different Populations ◽  
The Tropics

AbstractMorphological studies of different populations of what was previously considered to be a single species, Aphanogmus hakonensis Ashmead, revealed the presence of a complex of species which are extremely difficult to distinguish without detailed studies of male genitalia. Several of these species have been misidentified during biological control programmes or parasitoid surveys. These misidentifications are corrected, and two new species, Aphanogmus captiosus and Aphanogmus thylax are described. The hakonensis-complex is diagnosed. As far as is known, all species are hyperparasitoids of lepidopteran larvae via various hymenopteran or dipteran primary parasitoids.

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